Bis(salicyloyl) benzene derivatives and compositions containing the same



ited St te Pat 6 BIS(SALICYLOYL) BENZENE DERIVATIVES AND COMPOSITIONS CONTAINING THE SAME David A. Gordon, Midland, Micl1., assignor to The Dow Chemical Company, Midland, Micln, a corporation of Delaware N Drawing. Application December 1, 1955 Serial No. 550,478

2 Claims. (Cl. 26045.95)

This invention relates to new organic compounds and to polymeric compositions containing the same. More particularly, it relates to bis(chlorosalicyloyl) benzene and to polymeric compositions stabilized with the same.

Many polymers, such as haloethylene polymers, are subject to rapid and severe degradation and consequent discoloration upon exposure to sunlight. To overcome that disadvantage it has been found necessary to incorporate certain additives into compositions containing such polymers. Various compounds having a carbonyl group attached to a benzene ring in an ortho position to a hydroxyl group have been known to have utility as light stabilizers in such compositions. Several of those compounds, however, are oderiferous and volatile. Any odor in the stabilizer will be transferred to the stabilized composition tl'ius greatly reducing the merchandisability of any article prepared from the composition. Also, a volatile ingredient in a polymeric composition will gradually volatilize out of the composition leaving the composition unprotected.

Such compounds vary in their effectiveness for absorbing ultra-violet light and vary in their compatibility with the polymer employed in the composition. Thus, it is impossible to predict the efiectiveness of any particular compound as a light stabilizer for any given polymer.

It is accordingly the principal object of this invention to provide a new group of organic compounds having the stated utility.

It is a further object to provide a polymeric composition stabilized against the degradative efiects of light by means of such compounds.

The above and related objects are accomplished by means of certain ortho-bis(polychlorosalicyloyl) benzene derivatives having the general formula:

wherein n is a whole number of from 2 to 4. The invention additionally comprises light-stable thermoplastic compositions prepared by intermixing such compounds with haloethylene polymers.

The method of preparation of the compounds will be illustrated by the following preparation of ortho-bis(3,4,6- trichlorosalicyloyl) tetrachlorobenzene. One mole of di- '2,3,5-trichlorophenyl tetrachlorophthalate and a large ex- 2,824,853 Patented Feb. 25, 19,58

cess of A161 were ground and mixed and added to 1,13,2 tetrachloroethaue. The reaction mixture was heated "at 150 C. for 6 hours, then cooled, and dilute HCl added. The solvent was removed by steam distillation after which the residue was filtered. The product was then washed several times with dilute HCl following which it was stirred into cold 10 percent caustic, filtered, and the ketone reprecipitated with HCl. The ketone was ex tracted overnight with ethanol and dried. The product did not melt at temperatures up to 300 C. and was insoluble in most organic solvents such as ethanol, dioxane, chlorobenzene and methyl ethyl ketone.

The compounds were evaluated as light stabilizers for haloethylene polymers. Because of their low odor level they produced compositions which were more merchandisable than compositions prepared from previous stabilizers. In addition, their low volatility caused a more per-- manent stabilization than prior compounds.

As light stabilizers the compounds may be employed in an amount of from 0.5 to 6 percent by weight based on the weight of the polymer employed. It is possible to- A series of samples was prepared from basic formulation consisting of 95 parts of a copolymer prepared from percent vinylidene chloride and 15 percent vinyl chloride and 5 parts of acetyl triethyl citrate as a plasticizer. To some of the samples of the basic formulation was added an amount of a stabilizer of this invention. Another series of samples used Z-hydroxy-S-chlorobenzophenone, a known stabilizer, for comparative purposes, one of the samples was left blank. The amounts of stabilizer used in each sample is shown in the table. The samples were molded into sheets 0.01 inch thick and exposed for 3 months to direct sunlight in the State of Florida. After exposure the sheets were examined visually for darkening. The results are listed in the following table.

It can be seen that the derivatives of this invention;

provide appreciably greater protection to the polymer composition against the degradative effects of sunlight than does a known light stabilizer.

chloros'alicyloyl) tetrachlorobeniene characterized by hemethyl ethyl ketone; I V r r, OTHER REFERENCES.

Iclaimr" Y i' V. 7 4f 7 R ferences .Ciedinthe file oftlrisp'atem o 234 1851 'Adams Feb. 15 i944 V 7 mg a sohd meltmg at a temperature above 300 C. and r V V a v i V V I 7 being'ins'oluble in'rethallol, dioxfllle,ichlorobenz'eng a d 5 -'Houtman J n 123 19 8 V 2. A thermoplastic composition comprising" a halo- B H Ch r Ab mat 7 940 ethylene polymer and from 0:5 to 6.0 percent by weight ,f' 7 mm i 0 I j co ru zene. r 1 

2. A THERMOPLASTIC COMPOSITION COMPRISING A HALOETHYLENE POLYMER AND FROM 0.5 TO 6.0 PERCENT BY WEIGHT OF ORTHO-BIS (3,4,6-TRICHLOROSALICYLOYL) TETRA CHLOROBENZENE. 